Surveying instrument or range-finder.



A. M. BRIDGES. SURVEYING INSTRUMENT 0R RANGE FINDER.

APPLICATION FILED FEB. 20, 1912.

Patented Aug. 11, 1914.

Attorneys UNITED sraas rarest curios.

ANDREW M. BRIDGES, OF BOSTIC, NORTH GARGLINA, ASSTGNOR OF ONE-HALF TO GEORGE IVI. CHAPMAN, 0F RUSTIC, NORTH GABOLINA.

SURVEYING INSTRUMENT 0R RANGE-FINDER.

Application filed February 20, 1912.

To all whom it may concern Be it known that 1, ANDREW M. Bnioens, a citizen of the United States, residing at Bostic, in the county of Rutherford and State of North Carolina, have invented a new and useful Surveying Instrument or Range-Finder, of which the following 1s specification.

This invention relates to surveying in struments or range finders and has for its primary objectto provide a simple, con,- venient and eflicient means for determining or reckoning the distances of distant objects, inaccessible heights and depths, and the like.

With the foregoing and other objects in view which will appear as the invention is better understood, the invention resides in the novel construction and combination of parts elicited in the following description,

and pointed out in the appended claims, it

being understood that this invention is susceptible of alterations or deviations in its details within the scope of the appended claims without departing from the spirit of the invention.

The preferred embodiment of the inven tion is illustrated in the accompanying drawings, wherein similar reference char acters indicate similar parts and wherein Figure 1 is a perspective View of the instrument. Fig. 2 is a plan view thereof on a reduced scale and as inuse.

Referring in detail to the drawings, this instrument embodies a four-sided or rectangular frame 5, the upper edges of one pair of the parallel sides of which form straight edges let and 14 and which are provided with similar graduations 15 and 15 extending from one of the other sides. The upper edges 9 and 9 of the other sides of the frame are raised above the aforementioned straight edges. A beam 12 is slidalole and swingable on the straight edges 14: and 14' to and from the edge 9 from which the graduations 15 and 15 extend, and at the corresponding ends of the edge 9 and the beam 12 are arranged the bead sights 10 and 10 and at the other ends are arranged the respective split or notched sights 11 and 11, the respective pairs of sights 10 and 11 and 10 and 11 forming suitable sighting means to be brought into alinement with distant objects. The beam 12 is arranged to Specification of Letters Patent.

Serial No. 6?8,919.

slide and swing upon the straight edges 14 and 14 to and from the sighting means on the edge 9v and at various angles relative thereto. A. bar 13 is secured on the edges 9 and 9 intermediate the edges 14 and 14L and passes over and bears against the beam 12 at an intermediate point to retain the beam upon the frame, and a pair of adjusting rods 17 are pivoted to the beam 12 adjacent the respective ends thereof and are slidable loosely through the apertures or openings 16 in the side of the frame bearing the sighting means. The adjusting rods having their ends pivoted to the bottom of the beam, is of advantage, for the reason that the pivoted portions of the adjusting rod will serve to limit the endwise movement of the beam on the graduated edges. This frame 5 is also provided with a bot-- tom piece 7 which is adapted to be engaged by an upright 8 carried by a suitable tripod or other standard 6.

In use, the instrument is set at the position from which the measurement or measurements are to be taken, and the sighting means on the edge 9 is then brought into alinement with the object, to which object it is desired to determine the distance. The beam 12 is then slid and swung relative to, until the sighting means on the beam 12 is brought into alinement with the distant object, whereby the two sighting means are focused upon the object. The distance to the object thus focused is then readily calcu lated as follows. To compute the distance to the object focused, the reading on the scale 15 is divided by the differences in reading of the two scales and the quotion is multiplied by the distance between the two scales, the result being the distance to the object focused by the two sighting beams. It will be noted that the beam 12 being slidalole and swingable upon the straight edges 14 and 14 permits the beam to be adjusted more or less from the edge 9 and at various angles thereto, so that the two sighting means may be conveniently focused upon the object in order to provide the most convenient readings on the graduations 15 and 15, for cal culating the distance to the object focused. In this manner the instrument may be used as a surveying instrument and range finder, and may thus be utilized for determining or reckoning the distances to distant objects,

Patented Aug. 11, 191d.

the parallel straight-edge or graduations bemg known and providmg a sultable basis to or for determining the distances to inaccessible heights or depths, or for analogous purposes.

The adjusting rods 17 being slidable through one side of the frame 5 and being pivoted to the beam 12 permit the ready angular adjustment of the beam 12 relative to the sighting means on the said side, as well as an adjustment to and from the said side,

whereby the instrument may be conven iently employed for reckoning the distances to'distant objects by the use of the-parallel graduations 15 and 15, the distance between V determine the distances by ratio.

'An important and essential feature provided by the device, resides in the fact that the beam 12 is mounted loosely on the v straight edges so as to slide both longitudinally and laterally and to swing thereon, in

connection with the pair of adjusting rods 17 pivoted to the beams adjoining its ends and passing loosely through the frame below the sighting means carried by the frame, so that the adjusting rods may be slid and swung to variously adjust the beam. Thus,

7 and by adjusting one rod, one end of thef by sliding both of the adjusting rods, the

beam may be moved as a whole to and from the sighting means carried by the frame,

beam may be swung more or lesson the respective straight edge so as to bring the two 'spective ends thereof will be at proportionately small distances along the straight edges, so that a considerable transverse or lateral movement of the beam on the straight edges will result in i only a slight change in focus. In this manner, the focus may be adjusted to a nicety, which would not be possible by adjusting the rods by hand, that is, by sliding them back and forth. 'The beam may be quickly set by sliding the respective adjusting rods, and then may be set to final adjustment in a precise manner by swinging one of the adjusting rods. i

If desired, the notches sights 11 a d 11' maybe substituted'by field glasses or tele scopes, or by any other sighting means that may be desired or essential.

Havi g described the claimedjas new is:

invention, is

tangular frame, two opposite sides o A surveying instrument embodying are'c 5 which are raised above the others, a beam resting on the last mentioned sides, a bar secured on the raised sides intermediate the last mentioned sides and holding the beam uponthe last mentioned sides,the beam being movable between the raised sides, sighti'n means carried by one of the said raised si es,and

the beam, the secondinentioned sides being [graduated away from the said rai'sed side carrying the sighting means, and a pair of adjusting rods passing loosely through the said raised sideand pivoted to the bottom of thebeam, the pivotedportionsof the adjusting rods serving to limit the endw'ise movement of the beam.

; In testimony that I claim the foregoing asmy own, I havehere'to afiixed my signature in the presence of two witnesses.

. ANDREWM. BRIDGES;

Witnesses: v I

WV. B. MnmoN, Z. P. EARLY.

Copies of this patent may be obtained for five cents eachgby addressing the Goinniiss i one r ot re tents,

Washington). 0. 

